CN210228409U

CN210228409U - Novel degradable support

Info

Publication number: CN210228409U
Application number: CN201822051589.4U
Authority: CN
Inventors: Junyi Wang; 王君毅; Guohui Wang; 王国辉; Yinghong Zhao; 赵迎红; Tao Cai; 蔡涛; Chenchao Zhang; 张晨朝
Original assignee: Fuwai Hospital of CAMS and PUMC
Current assignee: Shanghai baixin'an Biotechnology Co.,Ltd.
Priority date: 2018-12-07
Filing date: 2018-12-07
Publication date: 2020-04-03
Anticipated expiration: 2028-12-07

Abstract

The utility model discloses a novel degradable support relates to and implants the medical instrument field, including interior muscle, polymer substrate layer and medicine layer, interior muscle is the wire that has the development function under the X-ray machine, the polymer substrate layer is formed by polymer solution mixture, and the parcel is in the wire periphery forms solid-state, has the polymer substrate layer of supporting role. The metal wires are twisted and woven to form a hollow twist-shaped structure. The utility model discloses combine together two kinds of substrates, provide one kind have good moulding, good radial support intensity, can develop completely the support. The utility model also provides a manufacturing method of the novel degradable bracket.

Description

Novel degradable support

Technical Field

The utility model relates to an implant medical instrument field, especially relate to a novel degradable support.

Background

Stents have gained wider and wider application in the field of cardiovascular disease as an important instrument for treating vascular stenosis. For the metal stent which is widely applied to clinic at present, as the metal stent is permanently remained in a human body after completing a treatment task, the metal stent has the defects of weakening MRI or CT images of coronary arteries, interfering surgical blood circulation reconstruction, blocking the formation of collateral circulation, inhibiting positive remodeling of blood vessels and the like. Based on these problems, biodegradable stents have attracted much attention as a possible alternative solution. The biodegradable stent is made of a degradable polymer material or a metal material. After the scaffold is implanted into a lesion part, the biodegradable scaffold can play a role in supporting blood vessels in a short time, so that the revascularization is realized. After the treatment is finished, the biodegradable stent can be degraded into organic matters which can be absorbed and metabolized by the human body in the human body environment, and finally the stent can disappear. In addition, the shelf life of the stent is short, which can affect the use of the stent, as the stent must be stored for a certain period of time after being prepared.

The degradable stent is made of absorbable metal and polymer, the density of the polymer material is low, the X-ray impermeability of the material is poor, the vascular stent prepared from the polymer is almost invisible under the assistance of medical imaging equipment and a digital subtraction technique, so that a doctor cannot accurately position the stent in the operation process, and therefore a developing mechanism needs to be additionally arranged on the polymer stent, so that the developing mechanism can be identified by the doctor under DSA. Namely, the lack of visibility of the stent base is compensated by the developing structure having good visibility.

In order to solve the problem of scaffold degradation, chinese patent 2014108566258 proposes a degradable iron-based alloy scaffold, but the iron-based scaffold itself has too low degradation speed, and needs to be doped with at least one of C, N, O, S, P, Mn, Pd, Si, W, Ti, Co, Cr, Cu, Re, and can be doped into pure iron to form the medical iron-based alloy. And various polymers are added to accelerate complete degradation, and degradation products are complex and easy to generate rejection reaction with blood vessels.

In order to improve the radial supporting strength of the stent, chinese patent 2017112132378 proposes a polylactic acid and its copolymer stent, which improves the radial supporting strength due to the high orientation in the radial direction, but greatly loses the toughness of the stent, so that the stent is easily broken after passing through the tortuous blood vessels.

To improve the development performance of the stent, chinese patent 2015103951018 proposes a blood vessel stent, which is filled with a developer on the surface or structure of the stent, but cannot achieve complete development of the entire stent

Accordingly, those skilled in the art have endeavored to develop a stent having good shaping, good radial support strength, and being capable of being fully developed.

SUMMERY OF THE UTILITY MODEL

In view of the above-mentioned defects of the prior art, the technical problem to be solved by the present invention is to develop a stent which has good shaping, good radial support strength and can be developed completely, and compared with the traditional degradable stent, the present invention uses a single base material, and combines two base materials, and ensures that the stent does not have restenosis by using the good radial support of the polymer; the good shaping of the metal wire is utilized, the stent is guaranteed not to be broken after reaching the pathological change through the tortuous blood vessels and being stretched, and the purpose of complete development of the whole stent is achieved.

In order to achieve the above object, the utility model provides a novel degradable support, including interior muscle, polymer substrate layer and medicine layer, its characterized in that, interior muscle includes the wire that has the development function under the X-ray machine, the quantity of wire is four or more than four, the polymer substrate layer is formed by polymer solution mixture, and the parcel is in the wire periphery forms and has the supporting effect the polymer substrate layer.

Further, the metal wire is one of an iron-based alloy, a magnesium-based alloy, a zinc-based alloy and an aluminum-based alloy.

Further, the cross section of the metal wire is in a cross shape.

Further, the metal wire is a single-cavity metal tube, so that the interior of the joint of the first substrate and the second substrate is of a hollow structure.

Further, the polymer substrate layer cross-sectional area is more than 10 times the cross-sectional area of the metal wire.

Furthermore, the metal wires are twisted and woven to form a hollow twist-shaped structure, the hollow structure of the hollow twist-shaped structure is formed by wrapping the plurality of metal wires around one prefabricated polymer wire for twisting and weaving, and after weaving is completed, the prefabricated polymer wire is degraded and removed.

The beneficial effects of the utility model reside in that: the utility model combines the advantages of good plasticity of the metal degradable stent and good supportability of the polymer degradable stent, improves the supportability relative to the metal degradable stent and is not easy to cause restenosis in blood vessels; compared with the polymer degradable stent, the polymer degradable stent has the advantages that the plasticity is improved, the stent fracture is not easy to occur, and the complete development can be realized. Adopt cavity fried dough twist structure can be so that in later stage polymer substrate layer parcel in-process, partial polymer can be in the imbedding fried dough twist structure to increase the firmness of parcel. Meanwhile, partial gaps are reserved in the operation process, the plasticity and the flexibility of the degradable stent are improved, and the degradable stent is beneficial to passing through pathological tissues.

The conception, the specific structure and the technical effects of the present invention will be further described with reference to the accompanying drawings, so as to fully understand the objects, the features and the effects of the present invention.

Drawings

Fig. 1 is a top view of the inner rib of the hollow twist structure according to a preferred embodiment of the present invention;

fig. 2 is a side view of the inner rib of the hollow twist structure according to a preferred embodiment of the present invention;

fig. 3 is an oblique view of the inner rib of the hollow twist structure according to a preferred embodiment of the present invention;

fig. 4 is a schematic cross-sectional view of a degradable stent composed of four metal wires according to a preferred embodiment of the present invention.

Detailed Description

The technical contents of the preferred embodiments of the present invention will be more clearly understood and appreciated by referring to the drawings attached to the specification. The present invention may be embodied in many different forms of embodiments, and the scope of the invention is not limited to the embodiments described herein.

In the drawings, structurally identical elements are represented by like reference numerals, and structurally or functionally similar elements are represented by like reference numerals throughout the several views. The size and thickness of each component shown in the drawings are arbitrarily illustrated, and the present invention is not limited to the size and thickness of each component. The thickness of the components may be exaggerated where appropriate in the figures to improve clarity.

In all the following embodiments, the metal wire 1 constituting the inner rib may be made of a material having a developing function under an X-ray machine, such as an iron-based alloy, a magnesium-based alloy, a zinc-based alloy, an aluminum-based alloy, or the like, or may be obtained by laser cutting a single-cavity metal tube, and the metal wire 1 may be a single metal wire or a plurality of metal wires arranged independently.

Example one

Fig. 1 is a top view of a hollow twist-shaped combination arrangement structure of a plurality of metal inner ribs according to a preferred embodiment of the present invention, wherein the metal wires 21 and the metal wires 22 are 2 of four metal wires with the same cross section. The preformed polymer filaments 23 are wrapped by four wires (including wires 21, 22) to form a bundle. Fig. 2 is a side view of the combination arrangement of the hollow twist-shaped inner ribs, fig. 3 is an oblique view of the combination arrangement of the hollow twist-shaped inner ribs, the inner ribs are arranged in a hollow twist-shaped combination manner, the combination arrangement of the twist-shaped combination manner can greatly improve the toughness of the support to avoid the support from breaking, but the flexibility of the support is lost. In this embodiment, a hollow twist-shaped arrangement method is designed, so that each metal wire has an independent moving space to make up for the loss in flexibility, and the specific implementation process is as follows:

step 1, selecting four or more metal wires with a developing function under an X-ray machine as inner ribs, and wrapping the plurality of metal wires (the plurality of metal wires in the embodiment are four wires such as 21 and 22 in fig. 1) around one prefabricated polymer wire 23 to form a bundle;

step 2, twisting the metal wire and the preformed polymer wire 23 together to weave a twist-shaped structure;

step 3, degrading the prefabricated polymer wire 23, and after removing the prefabricated polymer wire 23, forming a hollow structure in the middle of the twist-shaped structure to obtain a hollow twist-shaped structure inner rib;

step 4, coating a polymer solution on the surface of the inner rib of the hollow hemp-flower type structure, and forming a solid polymer substrate layer with a manufacturing shape after solidification;

and 5, covering a drug solution on the surface of the polymer base material layer to form a drug coating.

Example two

Fig. 4 shows a cross section of a four wire stand with independent wire arrangement according to another preferred embodiment of the present invention, and the manufacturing process of the present invention can be explained in detail by this embodiment. The inner ribs are four metal wires with the same material type and are independently arranged, and the metal wires 1 are iron-based alloy, magnesium-based alloy, zinc-based alloy and aluminum-based alloy which have a developing function under an X-ray machine; the metal wire 1 has good radial support performance and can ensure that restenosis can not occur by wrapping the polymer base material layer 2 formed by wrapping the polymer solution around the four metal wires, wherein the polymer solution is one or more of PLLA, PDLLA, PDLA, PLGA, PGLA, PLA and PDLGA, and the polymer base material layer 2 which is solid and has a support effect is formed by wrapping the polymer solution around the metal wires; the periphery of the polymer substrate layer 2 is covered with a medicine layer 3 mixed by medicine and polymer solution.

The polymer base material layer 2 can be obtained by spraying on the surface of the metal wire 1, and the specific implementation process is as follows: dissolving the polymer solution in one or more organic solvents of methanol, ethanol, isopropanol, acetone, tetrahydrofuran, acetonitrile and chloroform to form a spraying solution, fully oscillating and uniformly mixing, covering a layer of spraying solution with the thickness of 10-15um on the surface of the metal wire 1 at the spraying speed of 0.01-0.06mm/min, and then airing for 10min at the temperature of 20-25 ℃ and at the RH of 40-60%; spraying on the surface again, and repeating the steps until the polymer solution covers more than 10 times of the cross-sectional area of the metal wire 1; and (3) feeding the metal wire 1 sprayed with the spraying solution into a drying oven, and drying at the temperature of 10-20 ℃ lower than the glass transition temperature of the polymer solution material to form the polymer substrate layer 2.

The drug layer 3 can be obtained by spraying a drug solution on the surface of the polymer substrate layer 2, and the specific implementation process is as follows: dissolving the drug and the polymer solution in one or more organic solvents of methanol, ethanol, isopropanol, acetone, tetrahydrofuran, acetonitrile and chloroform to form a drug solution, fully oscillating and uniformly mixing, covering a layer of drug solution with the thickness of 5-10um on the surface of the polymer base material layer at the spraying rate of 0.01-0.03mm/min, sending the sprayed polymer base material into an oven, and drying at the temperature of 10-20 ℃ lower than the glass transition temperature of the drug solution material to form the drug layer 3.

EXAMPLE III

In this embodiment, the polymer substrate layer 2 may also be obtained by dip-coating the metal wire 1, and the specific implementation process is as follows: dissolving the polymer solution in one or more organic solvents of methanol, ethanol, isopropanol, acetone, tetrahydrofuran, acetonitrile and chloroform to form a dip-coating solution, and fully oscillating and uniformly mixing; immersing the metal wire 1 in the dip-coating solution, taking out and airing after 1min, turning the metal wire 1180 ℃ after airing, immersing the metal wire in the dip-coating solution again, taking out and airing after 1min, and ensuring that the dip-coating solutions at two ends of the metal wire 1 are coated uniformly; the coating thickness is 15-25um, and the positive and negative times are recorded as a cycle; then airing for 10min at 20-25 ℃ and 40-60% RH; repeating the above steps until the cross-sectional area of the wire 1 covered by the dipping solution is 0.01mm²To 0.04mm²To (c) to (d); and (3) feeding the metal wire 1 dipped with the dipping solution into an oven, and drying the metal wire at the temperature of 10-20 ℃ lower than the glass transition temperature of the polymer solution material to form the polymer substrate layer 2. In addition, the polymer substrate layer 2 can also be printed with the metal wire through 3D1 to obtain the compound.

The drug layer 3 can also be obtained by dip-coating the polymer substrate layer 2, and the specific implementation process is as follows: dissolving the drug and the polymer solution in one or more organic solvents of methanol, ethanol, isopropanol, acetone, tetrahydrofuran, acetonitrile and chloroform to form a drug solution, and fully oscillating and uniformly mixing; immersing the polymer substrate layer in the medicine solution, taking out after 1min, and airing; after airing, turning the polymer base material layer for 180 degrees, immersing the polymer base material layer in the drug solution again, taking out the polymer base material layer after 1min, airing to ensure that the drug solutions at two ends of the polymer base material layer are uniformly coated, adjusting the thickness of dip coating by controlling the concentration of the drug solution, wherein the coating is thicker when the concentration is higher, and is thinner when the concentration is lower; and (3) feeding the metal wire 1 dipped with the drug solution into an oven, and drying at the temperature of 10-20 ℃ lower than the glass transition temperature of the drug solution material to form the drug layer 3. In addition, the drug layer 3 may also be obtained by 3D printing the polymer base layer 2.

Example four

The metal wire 1 can also be a metal hollow pipe. The metal wire 1 formed by the metal hollow coffin can be cut in a 3D laser cutting mode by a spiral line in the axial direction or hollow in the radial direction (the hollow shape can be circular, directional, polygonal and various special shapes) on the surface of a tubular material, so that the aim of reducing the bending moment of a metal pipe is fulfilled. Compared with metal wire materials, the whole bending moment is greatly reduced, the flexibility of the whole stent structure is greatly improved, a polymer enters the hollow pipe through a processing gap of laser cutting on the hollow pipe in the subsequent polymer base material coating process, and the cohesive strength between the cured polymer base material and the metal base material is greatly improved.

The foregoing has described in detail preferred embodiments of the present invention. It should be understood that numerous modifications and variations could be devised by those skilled in the art in light of the teachings of this invention without undue experimentation. Therefore, the technical solutions that can be obtained by a person skilled in the art through logic analysis, reasoning or limited experiments based on the prior art according to the concepts of the present invention should be within the scope of protection defined by the claims.

Claims

1. The utility model provides a novel degradable support, includes interior muscle, polymer substrate layer and medicine layer, its characterized in that, interior muscle includes the wire that has the development function under the X-ray machine, the quantity of wire is four or four above, the polymer substrate layer is formed by polymer solution mixture, and the parcel is in the wire periphery forms and has the supporting effect the polymer substrate layer.

2. The novel degradable stent of claim 1 wherein said metal wire is one of an iron-based alloy, a magnesium-based alloy, a zinc-based alloy and an aluminum-based alloy.

3. The novel degradable stent of claim 1 wherein said wire has a cross-shaped cross-section.

4. The novel degradable stent of claim 1 wherein said metal wire is a single lumen metal tube.

5. The novel degradable stent of claim 1 wherein the cross-sectional area of the polymeric substrate layer is more than 10 times the cross-sectional area of the metal wire.

6. The novel degradable stent of claim 1 wherein said metal wires are twisted and braided in a hollow twist-type configuration, said hollow twist-type configuration being formed by wrapping said plurality of metal wires around a preformed polymer wire, twisting and braiding said plurality of metal wires, and degrading and removing said preformed polymer wire after braiding.